Sumatra 2004

Twenty years after the 2004 Indian Ocean tsunami

It is 7:58 a.m. (00:58 UTC) on 26 December 2004 when, in the Banda Aceh region of Indonesia, the earth start shaking: it is the beginning of one of the biggest disasters of the last 100 years.The shaking is very strong, causes numerous buildings to collapse and seems interminable. But the worst comes 20 minutes later when a tsunami of enormous proportions initially hits the coasts of northern Indonesia, with waves up to 30 metres high, and subsequently the entire Indian Ocean. The final toll is dramatic: over 250,000 dead and missing, including hundreds of European tourists on holiday in the varoius resorts.

The earthquake

Indonesia is one of the areas of the world where devastating earthquakes and volcanic eruptions occur most often. The huge Indonesian archipelago is particularly exposed to tsunamis due to its location along the edge of the Indian plate and the Burma plate, which move at a relative speed of about 60 mm/year. Due to this undercutting process of the Indian plate, called 'subduction', Indonesia is also among the most important volcanic areas in the world, with more than 100 active volcanoes.

The devastating Mw 9.2 earthquake occurred as a result of the interaction between the Indian plate and the Burma plate (the Indian plate moves northwards and flows under the Burma plate). The boundary between these two plates is marked by a trench called the Sunda trench. During the earthquake of 26 December 2004, a significant part of the fault separating the two plates shifted over a length of more than 1,000 kilometres.

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The estimated magnitude Mw 9.2 places the Sumatra earthquake of 26 December 2004 as the third largest ever recorded by instruments (since the beginning of the 20th century), after Chile's Mw 9.5 (1960) and Alaska's Mw 9.2 (1964). In the weeks following the event, studies revealed the exceptional characteristics of this earthquake: never before had instruments recorded the rupture of a fault more than 1000 km long (a length comparable to the size of the entire Italian peninsula). And what is more, in an area which, due to its tectonic characteristics, had not previously been considered capable of producing earthquakes of this size.The data showed that the rupture of this gigantic fault had produced a permanent horizontal displacement of northern Indonesia relative to the Indian plate of several metres in a south-westerly direction. These data, together with the seismograms and marigrams recorded by the world networks, made it possible to determine the distribution of the displacement along the more than 1,000 km of the fault: in particular, the movement of the two plates was estimated to have reached 30 metres in two areas the size of Tuscany.

The Boxing Day Tsunami

While the Christmas festivities were in full swing and Boxing Day was being celebrated in the United States with many European tourists crowding holiday resorts, a catastrophic tsunami struck the coasts of Indonesia just 20 minutes after the quake, and in the following hours, those of the entire Indian Ocean, causing casualties and damage even thousands of kilometres away from the epicentre.

26 December 2004, 7.58 a.m. (local time) Le onde di tsunami si propagano rapidamente per tutto l’Oceano Indiano: inizialmente, le acque si ritirano rapidamente lungo la costa settentrionale di Sumatra, ma questo segno di avvertimento non viene riconosciuto dalle popolazioni locali.

8:13 a.m. The Pacific Tsunami Warning Center (PTWC) in Honolulu, Hawaii, registers the earthquake and identifies the potential tsunami risk. However, since there is no specific warning system for the Indian Ocean, no formal notices or warnings are sent to coastal countries in the region. The lack of an early warning network will prove to be one of the main causes of the dramatically high number of casualties

8:17-8:27 a.m. The first waves of the tsunami, over 30 metres high, reach the coast of Banda Aceh on the island of Sumatra. The impact is devastating: entire towns and villages are submerged and destroyed within minutes. Infrastructure is swept away, and tens of thousands of people are swept away by the waves, which crash with immense force. Many victims are taken by surprise and are unable to escape the speed and overwhelming force of the waves.

9:28 a.m. One hour later, southern Thailand is hit by the tsunami. Tourist resorts such as Phuket, Krabi and Khao Lak, famous for their beaches, are hit hard. The tsunami also hits the far south of Burma (Myanmar) hard and pictures of the destroyed coastline quickly go around the world, showing the level of devastation caused by the disaster.

9:58 a.m. The energy carried by the tsunami hits the coast of Sri Lanka, about two hours after the quake. In particular, the north-eastern and southern coasts of the island are completely swept away by the waves, which destroy villages and coastal communities. Shortly afterwards, the waves also hit the east coast of India, starting from the city of Chennai in Tamil Nadu. The tidal waves penetrate inland for several kilometres, destroying infrastructure and dragging thousands of people with them.

13:00 Tsunami reaches the Maldives archipelago. The tidal wave sweeps over the capital Malé, flooding two-thirds of the city. Most of the Maldives' 1,192 islets are partially submerged, and many tourist facilities suffer extensive damage.

16:00 The tsunami waves continue their course across the Indian Ocean, reaching the east coast of Africa over 5,000 kilometres away. Somalia is the worst affected, where more than 300 people lose their lives. Casualties and damage to coastal infrastructure are also reported in Tanzania and Kenya. After 16 hours, tsunami waves even reached Struisbaai, South Africa.

18:00 The abnormal sea level changes also reached Mauritius, in the southern portion of the Indian Ocean. Although the island is not seriously damaged and no casualties are reported, the impact of the waves is nevertheless felt through material damage along the coastline. The tidal wave even reaches Antarctica, where tide gauges record consecutive oscillations of up to one metre in height for many days.

Yesterday & today

Satellite images and on-site measurements show that in the Indonesian province of Banda Aceh, which was most affected by the tsunami, the flooding reached a topographical height (runup - maximum height reached by water during a tsunami in relation to sea level) of about 35 metres, penetrating more than 4 kilometres inland. Along the coast of Thailand, to the east of the fault, the sea receded for about 20 minutes, leaving several hundred metres of beach dry, then returned and inundated the coast with runup heights of up to 18 metres.

Left, some of the damage caused by tsunami waves in Thailand (source UKRI - https://www.ukri.org/); right, some fishing nets hanging from trees (source: Joseph Trainor, University of Delaware, Disaster Relief Centre)

In these images taken from the story maps 'Boxing Day 2004 tsunami: then and now' produced by ESRI UK, you can see some satellite images showing the redevelopment after 10 years (in December 2014) of some of the areas most affected by the 26 December 2004 tsunami such as Lhok Nga and Banda Aceh.

Lhok Nga is a town in Indonesia, located on the western side of the island of Sumatra, 13 km south-west of Banda Aceh. A lone mosque that survived the devastating tsunami can be seen among the ruins of the town. The mosque has become a symbol of the tsunami destruction (Images provided by DigitalGlobe).

Banda Aceh is the capital and the largest city of Aceh Province, Indonesia. It is located on Sumatra Island  and has an altitude of 35 m. The 2004 tsunami killed more than 130,000 people in Aceh province and left more than 500,000 displaced.

The area hit hardest by the tsunami was precisely that of the Indonesian province of Banda Aceh where the flood reached a topographic altitude (runup) of approximately 35 metres, penetrating the hinterland for more than 4 kilometres.

The image on the left shows the devastating impact of the tsunami immediately after the arrival of the wave: dragging the scroll tool to the right shows the redevelopment of the area in December 2014.

No alert

The devastating tsunami of 26 December 2004 was one of the biggest disasters of the modern era. It had significant consequences not only for the regions directly affected, but also for global crisis management and disaster preparedness. The tsunami triggered a number of crucial changes in emergency management, highlighting the need for effective coordination of warning and relief operations.

A tsunami warning system, such as the one that was already in place in the Pacific Ocean (PTWS), could have saved the lives of many thousands of people who died for the tsunami in the Indian Ocean. The countries affected by the tsunami, including India, Thailand, Indonesia, and Sri Lanka, did not have a system in place to warn the population of the arrival of the destructive waves and induce them to move inland. 

The 2004 tsunami accelerated the development and strengthening of early warning systems in several regions, including the Indian Ocean, the Mediterranean, and the Caribbean, leading to the creation of three new Tsunami Warning Systems covering the whole world, among which one for the North Eastern Atlantic, Mediterranean and connected seas Tsunami Warning and MItigation System (NEAMTWS) and the INGV Tsunami Warning Centre!

2005 A new global focus

The World Conference on Disaster Risk Reduction, held in Kobe, Japan, and the Ministerial Meeting on Regional Cooperation on Tsunami Early Warning Arrangements, held in Phuket, Thailand, attracted increasing international attention after the 2004 Indian Ocean tsunami.

2005 A mandate for global tsunami safety

In response to the Indian Ocean tsunami, the Intergovernmental Oceanographic Commission of UNESCO (UNESCO-IOC) received a mandate from the international community to establish regional tsunami early warning systems. During the 23rd session of the UNESCO-IOC General Assembly, the following three TWS were created: - The Intergovernmental Coordination Group for the Tsunami and Other Coastal Hazards Warning System for the Caribbean and Adjacent Regions (ICG/CARIBE-EWS); - The Intergovernmental Coordination Group for the Tsunami Warning and Mitigation System in the Indian Ocean (ICG/IOTWMS); - The Intergovernmental Coordination Group for the Tsunami Early Warning and Mitigation System in the Northeast Atlantic, Mediterranean and Related Seas (ICG/NEAMTWS).

The map illustrates the area of coverage for each of the four Intergovernmental Coordination Groups (ICGs) for tsunami warning systems (CARIBE-EWS, IOTWS, NEAMTWS, PTWS) and also the Areas of Operation of Tsunami Service Providers (2016 update).

2013 Tsunami Warning Centre (CAT)

Italy has actively participated in the NEAMTWS since its inception in 2005. The first Session of the NEAMTWS was held in Rome in 2013, and the INGV Tsunami Warning Centre (CAT) was established to monitor and manage tsunami risk. The CAT was recognised as a 'tsunami service provider' by UNESCO in 2016, after demonstrating its ability to monitor large potentially tsunamigenic earthquakes (which cause about 80% of tsunamis), follow their evolution and communicate warnings to the Civil Protection Department in a timely manner, following internationally shared standards.

2015 The Tsunami Ready Programme

The guidelines for the recognition of the Tsunami Ready Programme are approved by the UNESCO-CIO General Assembly.

2017  National Alerting System for Tidal Tremors (SiAM) 

On 1 January 2017, the CAT-INGV became fully operational, as established in the agreement with the National Department of Civil Protection (DPC). On 17 February of the same year, CAT was formally designated - through a Prime Minister directive - as a component of SiAM - the National Alerting System for Earthquake-generated tsunamis in the Mediterranean Sea, coordinated by the National Civil Protection Department (DPC) and composed of CAT-INGV and the Istituto Superiore per la Protezione e la Ricerca Ambientale (ISPRA). ISPRA plays a fundamental role as it manages the sea level monitoring networks, including the National Mareographic Network (RMN), which is also very important for real-time monitoring of tsunamis, in particular allowing confirmation or cancellation of tsunami alerts.

2020 The evolution of tsunami monitoring stations in Italy

The National Mareographic Network is currently composed of 37 measurement stations (tide gauges), uniformly distributed along the coasts of the national territory and in the smaller islands (Lampedusa, Ginostra, Elba, Tremiti).  These stations are mainly located inside ports and carry out accurate and continuous monitoring of weather parameters (wind and atmospheric pressure) and sea level fluctuations due to both the astronomical tide cycle and other causes (such as storm waves or tsunamis).

2024 First Italian Municipality Tsunami Ready

Italy, with the Municipality of Minturno (LT), was one of the first coastal community  in the Euro-Mediterranean area (NEAMTWS), and the first in Italy, to adopt the UNESCO Tsunami Ready programme that fosters synergy between the parties involved, starting from the institutional sphere to the territorial bodies responsible for managing and safeguarding the territory, to Civil Protection (at various levels) and the involvement of local operators (owners of tourist facilities and coastal services) and stakeholders.

Stories

The Sumatra tsunami of 2004 was a catastrophic event that affected a vast area, affecting numerous territories and an impressive number of people even thousands of kilometres away. Each of the survivors has a story to tell. Some of them have been selected to be directly told with the support of pictures and videos. Their experiences can teach us all something.

“All disaster witnesses want to forget because it is painful. But they need to remember, to mitigate future risks”

1

Song of the Smong

As the tsunami approached the island of Simeulue, located 60 km from the epicenter of the earthquake (Simeulue is located in the Aceh district in the Mentawai archipelago northwest of Sumatra), the words 'Smong! Smong!" a term that in the indigenous local language means tsunami or chaos (it can be used in both meanings, it is a word that the Simeulue community uses only in the case of an event that could harm the community itself). As soon as they heard it, most of the inhabitants of the island of Nias started to head for the mountains shouting "Smong! Smong!" to spread the news. The inhabitants of the island of Simeulue have been learning a traditional song called 'Smong' since their childhood. This song, passed down from generation to generation after the 1907 tsunami, teaches that: "When there is a strong earthquake with an ocean withdrawal, don't go to the coast to collect fish, because a tsunami will come. When the ocean recedes, run for safety to the mountains. Take children, parents and women and run away from the beach. Shout, Smong, Smong'. The lyrics of the song clearly describe what to do in case the precursor signs of a tsunami are recognized. The song was handed down from father to son and became part of popular traditions. On Simeulue island, only seven people out of 78,000 inhabitants lost their lives. A very small number even compared to the multitude of human losses that occurred in other Indonesian areas.

2

Mary Yuranda

The story of Mary Yuranda, a young girl who survived the 26 December 2004 tsunami in Indonesia, is a tale of hope and family reunion. Little Mary, called Wati, was seven years old when the violence of the tsunami invaded the streets of Meulaboh, in Aceh province on the island of Sumatra, the worst hit by the tsunami. The child was walking with her mother Yusnidar and an older sister, and they were swept away by the impetus of the tsunami. Left for dead after the massive wave, Mary returned home to her village in Aceh district after seven years, recognised by her grandfather Ibrahim thanks to some distinctive marks on her body. During her absence, Mary had experienced hard times, forced by a woman to beg, but had managed to escape and return home, thanks to the help of a generous taxi driver. Her family, in despair after losing another daughter, experienced an emotional reunion, making Christmas 2011 an extraordinary time in remembrance of the past calamity.

3

Arif e Jannah

The Rangkuti family experienced a 'double miracle'. Ten years after losing their children in the devastating 2004 tsunami, Jamiliah and Septi were finally able to re-embrace their children Arif and Jannah. After several initial searches, the parents had given up. In June 2014, however, thanks to her uncle who, during a walk noticed a striking resemblance of a now girl to her niece. Asking around, it turned out that this girl was indeed Jannah. Surprisingly, a few months later, Arif was also found, thanks to a phone call reporting his presence in Payakumbuh, where he had been taken in by a couple. This extraordinary family reunion was completed thanks to the determination and never-failing hope of his parents.

4

Martunis

Martunis was eight years old on the day of the tsunami on 26 December 2004. That morning he was playing football on the beach at Banda Aceh in Indonesia with his friends. When the wave came he clung to a mangrove tree to save himself and survived in that tree for three weeks eating instant noodle packs and drinking bottles of water carried by the waves. When he was found, he was wearing footballer Rui Costa's jersey. Thanks to the Save the Children staff, Martunis was reunited with his surviving father, a fish and shrimp farmer, while his mother and siblings were never found. His story went around the world, and when players Rui Costa and Christiano Ronaldo visited Indonesia, they invited him to spend 15 days in Portugal. In 2015, Sporting Lisbon decided to sign him in the youth team to give him a chance to become a professional footballer. Martunis says "since I was little, I have loved playing football. Football is part of my life and I really enjoy playing it. One day I hope to become a professional footballer”.

5

Train #50 Matara Express

Among the tragic events that occurred on 26 December 2004 was the disaster of passenger train No. 50, known as the Matara Express, which was swept away by tsunami waves while travelling along the coastal railway line. The force of the waves destroyed the train, causing the death of most of the passengers on board. The account of the disaster is recounted as follows: 'At 9.30 a.m., in the village of Peraliya, near Telwatta, the first of the gigantic waves generated by the earthquake was observed on the beach. The train stopped as the water rose around it and the alarm sounded to warn the population of the rising water level. Hundreds of locals, believing that the train was safe on the tracks, climbed onto the roof of the carriages to avoid being swept away. Others took refuge behind the train, hoping thus to be protected from the force of the water. The first wave flooded the eight carriages and caused panic among the passengers. Ten minutes later a huge wave lifted the train and pushed it against the trees and houses that lined the tracks, crushing those who had sought shelter behind it. The passengers on top of the train were swept away and most of them drowned or were crushed by the debris. Locomotive No. 591 Manitoba was carried 100 metres (330 feet) away, stopping in a swamp.

6

Mangroves

Mangrove forests helped save many lives during the 2004 Sumatra tsunami disaster. This was the finding of a study conducted by the World Conservation Union (IUCN) that compared the death toll of two Sri Lankan villages hit by the devastating tsunami waves. Only two people died in the settlement surrounded by dense mangrove forest and scrub, while up to 6,000 people died in the village without similar vegetation. Many forests had unfortunately been cut down in the past to build shrimp farms and tourist resorts. Research has shown that mangroves can absorb between 70 and 90 per cent of the energy of a normal wave. There is, however, no reliable data on how trees mitigate the impact of a tsunami. Many people living in coastal areas now want to see their communities benefit from the apparent protection offered by mangrove forests.

7

Tilly Smith

Molto significativa la storia di Tilly Smith, una bambina inglese di 9 anni, che nel 2004 era in villeggiatura a Phuket in Thailandia insieme alla sua famiglia. Aveva imparato a conoscere gli tsunami alla Danes Preparatory School di Oxshott, nel Surrey, durante la lezione di geografia, due settimane prima del disastro. Grazie a questi insegnamenti riuscì a mettere in salvo circa 100 persone sulla spiaggia di Mai Khao Beach, dopo aver visto il mare ritirarsi per centinaia di metri e ribollire. Fu così in grado di avvisare i genitori, le altre persone presenti sulla spiaggia e il personale dell'hotel dove alloggiava; il suo allarme venne fortunatamente ascoltato dai bagnanti che trovarono riparo ai piani alti delle strutture turistiche. La spiaggia di Mai Khao Beach fu così evacuata prima che lo tsunami raggiungesse la riva e fu l'unica spiaggia thailandese in cui non si registrarono vittime. Il 3 novembre del 2005 Tilly e la sua famiglia visitarono la sede centrale delle Nazioni Unite, incontrando l’ex-presidente degli Stati Uniti Bill Clinton, inviato speciale dell’ONU per la ricostruzione. “La storia di Tilly dimostra quanto sia importante insegnare alle giovani generazioni tutto quanto concerne i disastri naturali”. Bill ClintonThe story of Tilly Smith, a 9-year-old English girl, who was on holiday in Phuket, Thailand with her family in 2004, is very significant. She had learnt about tsunamis at Danes Preparatory School in Oxshott, Surrey, during geography class two weeks before the disaster. Thanks to these lessons, she was able to rescue around 100 people on Mai Khao Beach after seeing the sea receding hundreds of metres and boiling over. She was thus able to warn his parents, the other people on the beach and the staff of the hotel where she was staying; her alarm was fortunately heard by the bathers who found shelter on the upper floors of the tourist facilities. Mai Khao Beach was thus evacuated before the tsunami reached the shore and was the only Thai beach where no casualties were reported. On 3 November 2005, Tilly and her family visited UN headquarters and met with former US President Bill Clinton, the UN Special Envoy for Reconstruction. Clinton commented "Tilly's story shows how important it is to teach the younger generation all about natural disasters".

8

María Belón

On 26 December 2004, María Belón was enjoying a heavenly holiday in Khao Lak, Thailand, with her husband and children, on a day of sunshine, games and quiet reading by the pool. When the birds began to fly away in terror and a loud roar was heard, she knew something was wrong. A 'black monster', as tall as a palace, rose up before her eyes, as tourists and hotel workers ran and palm trees fell behind them. At that moment she certainly could not have imagined that they would become the Spanish family that survived the terrible Sumatra-Andaman tsunami. Her story was immortalised in the award-winning film 'The Impossible', directed by J.A. Bayona. Despite the physical and psychological wounds that her family has faced over time, María Belón speaks of the experience as a 'gift' of life: 'There is a moment when you have to decide whether that complicated pain, situations you have never experienced, post-traumatic shock... There is a moment, like a crossroads in your life, when you say: 'What do I do? Do I remain a victim? Do I victimise myself for the rest of my life? Or do I choose the other way?'. There are no half-ways. And this other way is to say: "What do I do to learn what life wants to teach me?".

9

Roberto Vettori

Roberto Vettori, real estate agent from Pesaro (Italy), escaped the tsunami that swept Indonesia on 26 December 2004. He was in Thailand with his partner to celebrate Christmas. They were staying on Phuket Island, in Patong, right by the sea. "The holiday was one of those dream holidays that was about to turn into a nightmare" he pauses and smiles "no, not the tsunami (not yet) but a non-functioning shower that saved our lives". "After two days of discomfort due to a broken shower that seemed like irreparable damage, we decided to change hotel. Armed and packed after breakfast, at about 8 a.m., woken up by an earthquake tremor (I didn't pay much attention to it, it happens a lot in those countries), we moved a few metres to look for another hotel, not an easy feat at Christmas time. As we haggled our way with the tuk tuk taxi driver (a picturesque three-wheeled taxi used mostly in Southeast Asia), I noticed the sea smooth as oil with a huge white wall towering behind it. Oh my God, that was a tsunami! Knowing the places, also thanks to the excursions of the days before, I told the taxi driver to take the first road on the left towards the hill. In the meantime, I later learned, the wave travelling at 400 km per hour was going to sweep over the island at 10 o'clock. And so it unfortunately did". "We found shelter 300 metres above sea level on a rubber collector's farm where, a little later, dozens of wounded arrived".

The map illustrates the area of coverage for each of the four Intergovernmental Coordination Groups (ICGs) for tsunami warning systems (CARIBE-EWS, IOTWS, NEAMTWS, PTWS) and also the Areas of Operation of Tsunami Service Providers (2016 update).